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Impact of drift, tilt and tilt susceptibility on CG-6 gravity observations
Subject area: Science,Engineering and Technology · Area of research: Geoscience
Abstract
Scintrex CG-6 gravity meter is the state-of-the-art technology of modern gravity observations and used for high precision gravity surveys. It provides four types of automated corrections: drift; tilt; tide and temperature. The tilt susceptibility is a phenomenon when transporting the equipment without its upright position and observations without initial settlement. This research investigates the impact of drift, tilt and tilt susceptibility on gravity observations. Different conditions were considered to achieve more accurate results and to introduce better recommendations for users in order to minimize the effects. The closed loop sequence technique was used to identify the necessity of performing drift calibration tests and to study drift characteristics. The impact of tilt on gravity readings was investigated by changing the X and Y level range manually. Tilt susceptibility was experimented by changing the tilt duration. According to the analysis, it was noted that drift varied linearly (R2 ? 1) with time, so linear drift assumption is compatible with simple observable procedure. Automated tilt correction is proportional to X and Y level range and a significant dislevellment of the instrument caused inaccurate results. It was revealed from tilt susceptibility test that the instrument must be settled before starting the observations and the settlement time depends on the tilting duration. In order to predict the recovery time of the instrument, liner and polynomial function models were implemented and the linear model shows that the predictions could be made to a higher degree of certainty.
Keywords
Gravity; Drift; Tilt; Tilt Susceptibility
References
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[12] Weerasinghe PIA, Prasanna HMI. Temperature and humidity effects on CG-6 gravity observations, Journal of Applied Geodesy, 2021. https://doi.org/10.1515/jag-2020-0047.
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[14] Figure Captions
[15] Table Captions
How to cite this paper
@article{1703074,
author = {M.P.G. Iresha, H.M.I.Prasanna},
title = {Impact of drift, tilt and tilt susceptibility on CG-6 gravity observations},
journal = {Iconic Research And Engineering Journals},
year = {2021},
volume = {5},
number = {6},
pages = {191-199},
issn = {2456-8880},
url = {https://www.irejournals.com/formatedpaper/1703074.pdf},
abstract = {Scintrex CG-6 gravity meter is the state-of-the-art technology of modern gravity observations and used for high precision gravity surveys. It provides four types of automated corrections: drift; tilt; tide and temperature. The tilt susceptibility is a phenomenon when transporting the equipment without its upright position and observations without initial settlement. This research investigates the impact of drift, tilt and tilt susceptibility on gravity observations. Different conditions were considered to achieve more accurate results and to introduce better recommendations for users in order to minimize the effects. The closed loop sequence technique was used to identify the necessity of performing drift calibration tests and to study drift characteristics. The impact of tilt on gravity readings was investigated by changing the X and Y level range manually. Tilt susceptibility was experimented by changing the tilt duration. According to the analysis, it was noted that drift varied linearly (R2 ? 1) with time, so linear drift assumption is compatible with simple observable procedure. Automated tilt correction is proportional to X and Y level range and a significant dislevellment of the instrument caused inaccurate results. It was revealed from tilt susceptibility test that the instrument must be settled before starting the observations and the settlement time depends on the tilting duration. In order to predict the recovery time of the instrument, liner and polynomial function models were implemented and the linear model shows that the predictions could be made to a higher degree of certainty.},
keywords = {Gravity; Drift; Tilt; Tilt Susceptibility},
month = {December},
}